We evaluated the accommodative response to a stimulus moving from 0 6 D following staircase function under natural, corrected, and induced optical aberrations, using an adaptive-optics (AO) electromagnetic deformable mirror. The of eye (through mirror) change aberrations were measured on 5 subjects Hartmann–Shack wavefront sensor operating at 12.8 Hz. Five conditions tested: (1) natural (2) AO correction unaccommodated state induction (over 6-mm pupils) (3) +1 μm (4) −1 spherical aberration...

We evaluated the visual benefit of correcting astigmatism and high-order aberrations with adaptive optics (AO) on acuity (VA) measured at 7 different luminances (ranging from 0.8 to 50 cd/m2) two contrast polarities (black letters white background, BoW, black WoB) subjects. For BoW condition, VA increased background luminance in both natural AO-corrected conditions, there was a AO correction all (by factor 1.29 average across luminances). WoB foreground but decreased for highest luminances....

We present an optimization method to retrieve the gradient index (GRIN) distribution of in-vitro crystalline lens from optical path difference data extracted OCT images.Three-dimensional images are obtained in two orientations (with anterior surface up and posterior up), allowing obtain geometry.The GRIN reconstruction is based on a genetic algorithm that searches for parameters 4-variable model best fits distorted lens.Computer simulations showed that, noise 5 µm elevations, recovered with...

Custom high-resolution high-speed anterior segment spectral domain optical coherence tomography (OCT) was used to characterize three-dimensionally (3-D) the human crystalline lens in vivo. The system provided with custom algorithms for denoising and segmentation of images, as well fan (scanning) (refraction) distortion correction, provide fully quantitative images posterior surfaces. method tested on an artificial eye known surfaces geometry a vitro, demonstrated three lenses Not correcting...

We measured the effect of correction natural aberrations eye by means adaptive optics on subject's performance three different visual tasks: subjective sharpness assessment images, familiar face recognition, and facial expression recognition. Images were presented through a dedicated psychophysical channel viewed an electromagnetic deformable mirror. Experiments performed 17 normal subjects. Ocular (astigmatism higher order aberrations) reduced average from 0.366 ± 0.154 to 0.101 0.055 μm...

Abstract Most tunable lenses (TLs) are affected by deviations in optical power induced external temperature changes or due to internal heating while use. This study proposes: (1) An experimental characterization method evaluate the magnitude of shifts; (2) three different mathematical models (experimental, polynomial, and optimized) describe response lens with temperature; (3) predictions shifts using time frames minutes, seconds, milliseconds and; (4) a real compensation tool based on...

Custom high-resolution high-speed anterior segment spectral domain Optical Coherence Tomography (OCT) provided with automatic quantification and distortion correction algorithms was used to characterize three-dimensionally (3-D) the human crystalline lens in vivo four subjects, for accommodative demands between 0 6 D 1 steps.Anterior posterior radii of curvature decreased demand at rates 0.73 0.20 mm/D, resulting an increase estimated optical power eye 0.62 per diopter demand.Dynamic...

Custom high-resolution high-speed anterior segment spectral domain Optical Coherence Tomography (OCT) was used to characterize three-dimensionally (3-D) corneal topography in keratoconus before and after implantation of intracorneal ring segments (ICRS). Previously described acquisition protocols were followed minimize the impact motions eye. The collected set images corrected from distortions: fan (scanning) optical (refraction). algorithms developed for automatic detection classification...

Fast tunable lenses allow an effective design of a portable simultaneous vision simulator (SimVis) multifocal corrections. A novel method evaluating the temporal profile lens in simulating different intraocular (M-IOLs) is presented. The proposed involves characteristic fitting through-focus (TF) optical quality component given M-IOL to linear combination TF monofocal viable with lens. Three types designs are tested, namely: segmented refractive, diffractive and refractive extended depth...

Tunable lenses are becoming ubiquitous, in applications including microscopy, optical coherence tomography, computer vision, quality control, and presbyopic corrections. Many require an accurate control of the power lens response to a time-dependent input waveform. We present fast focimeter (3.8 KHz) characterize dynamic tunable lenses, which was demonstrated on different models. found that temporal is repetitive linear, allowed development robust compensation strategy based optimization...

Abstract Multifocal contact lenses (MCLs) are one of the solutions to correct presbyopia, but their adoption is not widespread. To address this situation, visual simulators can be used refine adaptation process. This study aims obtain accurate simulations for a simulator (SimVis Gekko; 2EyesVision) daily soft MCL designs from four manufacturers. In-vitro characterization these MCLs—several powers and additions- was obtained using NIMO TR-1504. From averaged relative power profiles across...

To propose a method to correct optical coherence tomography (OCT) images of posterior surface the crystalline lens incorporating its gradient index (GRIN) distribution and explore possibilities for shape reconstruction in comparison existing methods correction.Two-dimensional nine human lenses were obtained with time-domain OCT system. The was corrected using proposed iterative correction method. parameters defining GRIN used taken from previous publication. results evaluated relative...

Purpose: As multifocal contact lenses (MCLs) expand as a solution for presbyopia correction, better understanding of their optical and visual performance becomes essential. Also, providing subjects with the experience vision before lens fitting critical, both to systematically test different designs optimize selection in clinic. In this study, we evaluated ability simultaneous simulator (SimVis) represent MCLs. Methods: Through focus (TF) quality center-near aspheric MCL (low, medium high...

The Simultaneous Vision simulator (SimVis) is a visual demonstrator of multifocal lens designs for prospective intraocular replacement surgery patients and contact wearers. This programmable device employs fast tunable works on the principle temporal multiplexing. SimVis input signal tailored to mimic optical quality using theoretical profile, which evaluated from through-focus Visual Strehl ratio metric lens. In this paper, first time, focimeter-verified on-bench validations simulations are...

Abstract We present a new metric (Multifocal Acceptance Score, MAS-2EV) to evaluate vision with presbyopic corrections. The MAS-2EV is based on set of images representing natural visual scenes at day and night conditions projected in far near displays, stereo target. Subjects view score the through different binocular corrections (monofocal far; bifocal corrections; monovision modified monovision) administered soft contact lenses (in cyclopleged young subjects) or simultaneous simulator...

PurposeThe purpose of this study is to compare the binocular visual perception participants wearing multifocal contact lenses and these same lens designs viewed through a temporal multiplexing simulator.MethodsVisual performance perceived quality at various distances were obtained in 37 soft M−CLs SimVis Gekko programmed with lenses. In pilot (n = 10) was measured terms LogMAR acuity (VA) far (4 m), intermediate (64 cm) near (40 through-focus VA (TFVA) curves simulated M−CLs. follow-up 27),...

Whole-eye optical coherence tomography (OCT) imaging is a promising tool in ocular biometry for cataract surgery planning, glaucoma diagnostics and myopia progression studies. However, conventional OCT systems are set up to perform either anterior or posterior eye segment scans cannot easily switch between the two scan configurations without adding exchanging components account refraction of eye’s optics. Even state-of-the-art whole-eye systems, pre-selected be dynamically reconfigured. In...

Presbyopic intraocular lenses (IOLs) based on simultaneous vision represent a compromise between perceptual benefit and cost at near far distances. We evaluated this for simulated bifocal IOLs with varying energy distributions additions using SimVis Gekko under different adaptation conditions. Presenting multifocal corrections after blur an abrupt transition of least 5s improves acceptance. Smooth transitions to multifocality also improve acceptance, independently previous adaptation....

Abstract Multifocal contact lenses (MCLs) are one of the solutions to correct presbyopia, but their adoption is not widespread due factors such as discomfort, lack awareness, a lengthy fitting process and/or unexpected visual performance. To address this situation, simulators can be used aid in refining adaptation process. This study aims obtain accurate simulations for novel simulator (SimVis Gekko; 2EyesVision, Spain) various daily commercial soft MCL designs from four different...

Ocular degradation is frequently assessed convolving images with the ocular point-spread-function, estimated from wave-aberration. Comparisons of visual acuity measured using aberrated targets (viewed through adaptive-optics corrected aberrations) and under natural aberrations reveal consistent discrepancies.